Influence of Multiple Firing on the Bending Strength of Zirconia/Porcelain Bilayered Dental Ceramics
Bilayered three-point bending strength specimen of KAVO zirconia-Vita VM9 veneering porcelain were made according to ISO6872 standard, the core to porcelain thickness ratio was 1:1. Specimens were subjected to multiple dentine porcelain firing cycles. Three-point bending strength were tested, SEM was used to observe the characteristics of the failure mode. Results show that there was no influence on the bending strength by multiple firing, the three-point bending strength were 996 ~ 1020 MPa after multiple firing, and no obvious defects was found at the interfaces. In all bilayered specimen, the bulk fracture initiated at the tensile surface of the core material and was consistently accompanied with porcelain crush and delamination at the interface.
Yiwang Bao, Danyu Jiang, Li Tian and Jianghong Gong
R. J. Lu et al., "Influence of Multiple Firing on the Bending Strength of Zirconia/Porcelain Bilayered Dental Ceramics", Key Engineering Materials, Vol. 492, pp. 24-29, 2012